1. Field of the Invention
The present invention is the use of known oxazolidinones to treat psoriasis, arthritis and to reduce the toxicity of cancer chemotherapy.
2. Description of the Related Art
U.S. Pat. Nos. 5,164,510, 5,231,188, 5,565,571, 5,652,238 and 5,688,792 all disclose various oxazolidinone antibiotics which are well known to those skilled in the art.
Psoriasis is a well known condition, a proliferative disease of the skin of unknown etiology. It is not known, or believed, to have a microbiologic cause.
Problems experienced by those suffering with psoriasis include intense itching and discomfort, unsightly skin blemishes and chronic scratching resulting in skin infections.
At present there are no cures, only methods of dealing with the clinical symptoms experienced by the patients. These methods of treatment include avoiding drying of the skin and irritation of skin, use of topical steroid cremes and ointments, use of crude coal tar (1-5% in an ointment base) applied topically, ultraviolet light therapy, topical vitamin D (calcipitriol), oral methotrexate for severe cases (a drawback to this therapy is that methotrexate causes severe liver damage if not careful), use of etretrinate (a synthetic retinoid) for severe cases (however a drawback to this therapy is that it is associated with severe deformities in fetuses if a female patient is pregnant).
There is no cure for psoriasis, but rather treatments which may induce a remission for a period of time. Since the pathogenesis of psoriasis is unknown, the reason why the various treatments do not fully succeed is not known but it is likely that present treatments are not treating the root cause of psoriasis.
While there are number of pharmaceutical agents available for treating psoriasis, none treat the condition/disease as well as psoriasis sufferers or physicians would like.
Arthritis, inflammation of the joint tissues, has numerous causes including bacterial infection (septic arthritis), degeneration of articular surfaces (osteoarthritis), immunologic reaction against joint tissues (rheumatoid arthritis), crystal induced arthritis (gouty arthritis, pseudogout) and other miscellaneous causes (Reiter's syndrome, etc). One common thread in all of these is inflammation in and around the joint. Present day therapeutics for arthritis are not curative unless the arthritis is infectious and the underlying pathogen is eliminated by an antibiotic. For other types of arthritis medications can reduce pain or inflammation but do not cure the disease. The OXAZOLIDINONEs can be used to treat the inflammation and pain caused by arthritis, including those types of arthritis which are not caused by infection. This is important since all of the medications presently available to treat arthritis have severe side effects. Steroidal medications (glucocorticoids like prednisone and cortisol) give stomach ulcers, cataracts, reduced resistance to infection, weight gain and thinning of skin. Non-steroidal anti-inflammatory drugs (NSAIDS such as indomethacin or ibuprofen among others) can cause stomach ulcers, reduced kidney function and bone marrow effects. Chemotherapeutic agents (like methotrexate) can have severe adverse effects on bone marrow and liver function. The OXAZOLIDINONEs provide the opportunity for relief of symptoms of inflammation for patients intolerant of other types of arthritis medications.
Patients who have cancer and need to undergo anti-cancer chemotherapy have the problem that the dose limiting factor in their treatment is the suppression of bone marrow. The present invention prevents and reduces the amount of suppression of bone marrow and injury to intestinal crypt cells (the cells that produce new intestinal cells). By preventing damage to the hematopoietic cells in general and the bone marrow cells in particular, physicians can prevent or reduce the toxicity of the chemotherapeutic agents and therefore can treat cancer patients longer and/or with higher doses and with reduced risks of complications. All this means a more successful outcome for the patient.
At present there is no product on the market that prevents damage to hematopoietic and/or intestinal cells from exposure to anti-cancer chemotherapeutic agents. There are products which are given after anti-cancer chemotherapy to try and help the patient recover, but this is not the same as the preventive method of the present invention. These agents include bone marrow colony stimulating factors such as GM-CSF. There are protective agents known, but not in clinical use, for dealing with radiation therapy such as glutathione derivatives, but these do not prevent the problems associated with anti-cancer chemotherapy.